Ireland's embattled taoiseach, Brian Cowen, is issuing a "back me or sack me" challenge to backbenchers in Dublin today as speculation mounts that he may stand down as leader of Fianna Fáil.

Cowen's position is looking increasingly under threat after further revelations about his contacts with Anglo Irish Bank officials before the controversial bank guarantee in September 2008.

There were reports at the Dáil that a motion of no confidence against the taoiseach may be tabled by backbenchers at a crunch meeting of the Fianna Fáil parliamentary party this afternoon.

The meeting was arranged after requests from some TDs after more details emerged of Cowen's dinner with the former Anglo Irish Bank chairman Seán FitzPatrick at the Druids Glen golf complex in County Wicklow in July 2008. Anglo is regarded as one of the main culprits of the banking crisis and any association with its executives is highly damaging.

Fianna Fáil backbencher Mary O'Rourke dismissed the latest speculation, saying talk of a leadership heave was wide of the mark.

"It's far too late. I hate saying it, but we are where we are," she told Dublin Newstalk radio. "We are so near a general election that it would be futile I think to go changing anything."

Eighteen signatures of TDs and senators are required to force a vote on the party leadership.

One Fianna Fáil source said today that Cowen was already considering standing down as Fianna Fáil leader at the weekend but remaining as taoiseach until the Dáil dissolved and a general election was called.

This move by the backbenchers may precipitate that election, the Fianna Fáil source said.

"Instead of a planned move to elect a new leader in a smooth transition this rebellion risks pulling down the entire government," the source said.

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